Flu Season Off to Slow Start . . .

WEDNESDAY, Oct. 23 (HealthDay News) -- The 16-day federal government shutdown earlier this month hindered the ability of U.S. health officials to monitor flu activity around the country.

Turns out, there wasn't much to monitor because there haven't been many outbreaks of the infectious disease so far this fall, officials said.

But that could change at a moment's notice, noted the health officials, who are fond of saying that the only thing predictable about the flu is its unpredictability.

So far, there have been isolated cases of flu in Alabama, South Carolina and Texas, according to the U.S. Centers for Disease Control and Prevention.

"The flu has been pretty quiet right now," said Dr. Joe Bresee, chief of the epidemiology and prevention branch in the CDC's Influenza Division. "But flu is coming, it's right around the corner and we expect an increase to come in the next few weeks."

And now's a perfect time to get vaccinated, he said, adding, "it's never too late to get vaccinated."

Getting vaccinated is the best way to prevent the flu, and there's plenty of vaccine to go around, Bresee pointed out.

"We expect to have 135 to 139 million doses available, so there should be plenty of vaccine to vaccinate anybody who wants to be vaccinated," he said.

The number of Americans getting vaccinated has risen since the H1N1 pandemic flu in 2009, according to Bresee.

"It's edging up in most groups, which is really gratifying, especially in some of the high-risk groups like pregnant women and kids. We are seeing good gains over the last four or five years," he noted.

"But we have a long way to go," he added. "Still only half of Americans get vaccinated. Vaccine is still the single best thing folks can do to prevent flu."

It's too early to tell, however, whether this year's vaccine will be a good match for the flu strains that are circulating.

"As with most things with flu, we always hedge a little bit. We do know the vaccine is a good match for the strains that have circulated around the world and the U.S. over the summertime and that's a good sign. But we won't know really until we get into the season, but we think it will be pretty good," Bresee said.

Flu season typically starts in the fall and peaks in January and February.

Even if this season's vaccine isn't a perfect match, it can still be beneficial. Antibodies triggered in response to a vaccination with one flu virus can sometimes protect against different but related viruses, according to the CDC.

There are three kinds of flu viruses that are most common today: influenza A (H1N1) viruses, influenza A (H3N2) viruses, and influenza B viruses. According to the CDC, the 2013-2014 vaccine consists of the following three viruses:

an A/California/7/2009 (H1N1) pdm09-like virus;

an A(H3N2) virus antigenically like the cell-propagated prototype virus A/Victoria/361/2011;

a B/Massachusetts/2/2012-like virus.

Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City, said that, in addition to getting vaccinated, hand-washing and staying away from people with the flu are other ways of avoiding the disease.

For Horovitz, however, the take-home message is: "vaccinate, vaccinate, vaccinate."

Bresee said getting a flu shot not only prevents flu, which is bad enough, it can also head off complications from underlying chronic diseases.

For example, a study published Oct. 22 in the Journal of the American Medical Association found that people with heart disease who get a flu shot significantly reduce their risk of heart attack or stroke.

"In flu season a lot of the deaths or hospitalizations attributable to flu were probably triggered by a worsening of an underlying disease like a chronic lung disease or heart disease or diabetes," Bresee explained. "The idea is that if you prevent the flu, you also prevent the complications of those underlying diseases."

Horovitz said the flu vaccine doesn't prevent heart attacks or strokes. "But influenza is a severe viral illness that strains the body, so it wouldn't be surprising that preventing the flu can help ward off a further strain on the body," he said.

For the CDC, the recent government shutdown was a mixed bag, Bresee said. It didn't affect the flu vaccine program because the machinery to get the vaccine out and into clinics and pharmacies was already under way, he stated.

"Where the shutdown did affect us a bit was in our ability to do surveillance early in the season, which is a critical time to know what's happening with flu," Bresee said. "We kept up with surveillance to some extent, but we weren't able to look at all the data. We're catching up now and we're about up to date."